In eight months support for Scottish independence has increased by 10%. Some 41% favour independence compared to 43% who support the union according to a new poll out today. That's still a minority but it's clear where the momentum lies. As the New Labour project unravels, the movement for self-determination is the beneficiary.

The poll, conducted by Progressive Scottish Opinion for that dowdy defender of the UK, the Scottish Daily Mail, shows a surge in support for independence at a time of growing credibility for the SNP and a collapse in Labour support, north and south of the border. Wendy Alexander's colleague, Jackie Baillie, stated: "What Scots want is to walk tall in the union, not walk out." The trouble is with the ongoing dispute over Scotland's missing £400m in council tax benefit, withheld by London, missing millions in prison upgrade payments and now the refusal of the Treasury to accept the local income tax proposals on which the SNP were elected, "walking tall" is hardly the impression given right now.

From the putative "British" Broadcasting Corporations forking out £200m for formula one, but being unable to find the coppers to fund terrestrial coverage the Scottish football team, to the embarrassing exposés of the Scottish Media Commission, the media experience is also vastly imbalanced. Last year Ofcom confirmed that the BBC's recent spending in Scotland, which has 8% of the UK's population and 12% of government spending, had fallen by some £20m to 3% of its total. The very experience of Britishness, in the past brought to us partly through the media, is unravelling. What once united now divides.

On the tax issue, it's clear that people resent the Scottish government being treated like a Treasury department. SNP policy is for a local income tax to replace council tax, set at three pence in the pound. David Cairns has tried to block the move, declaring it outside the scope of the Scotland Act. Here's the crunch. Whether the Treasury are technically right or not, it's difficult to see how they can oppose the wishes of an elected government.

Nicola Sturgeon, deputy first minister, said: "The more the London Treasury lays down the law the greater the support will be for independence and equality for Scotland." She's right. London Labour must initiate the joint devolution committee that should oversee these disputes, then they will have to decide how to negotiate on these and a host of other issues.

As the prison and tax payments storm brews, other problems lie ahead for the unionist trio of Nicol Stephen, Annabel Goldie and Wendy Alexander. Core Labour voters beguiled by SNP populism and defence of civic institutions, NHS services and ideals are finding it difficult to reconcile Wendy's recently discovered socialism and her stepping out with the formidable but electorally negligible Goldie.

This week Henry McLeish, the former Labour first minister who has enjoyed something of a resurgence in credibility since leaving office, backed SNP plans for a referendum on independence. Alexander's own husband denounced the Treasury's new tax on whisky duty. Professor Brian Ashcroft, who runs The Fraser of Allendar Institute is famous for the lecture in which he declared independence to be "the best option" economically. Ashcroft said: "It is understandable that the Scotch whisky industry should be 'astonished' by Alastair Darling's decision." It may be convenient mythmaking to portray Darling and Brown as Scottish cuckoos running a cabal at Westminster, but it doesn't look like that north of Carlisle. With friends like these, Alexander doesn't need to look far for enemies.

The poll is interesting for other reasons. It confirms the trend - witnessed over many years and contradicted only by Goldsmith's recent Britishness review - that support for independence is strongest among the young and skilled workers (47% in favour). The over 65s and the better-off are less supportive. Those in the oldest and youngest age groups were least in favour, with 50% of those aged 65 and over against independence and 48% of those in the 18 to 24 age range also opposed.

But how will this support stand up against coming recession and economic uncertainty? Will the security of the union seem undermined, as the UK is hit as hard as any other country, or will the leap of faith needed for another 10% to shift to independence seem impossible under the weight of economic fears and frailty? The real point of interest is with the 16% who - when given a straight choice - remain undecided.

If in another eight months - by Christmas - another 5% have shifted across to support independence, support for a referendum - currently at 85%, will be unstoppable.